1. Field of the Invention
The present invention relates to a multilayered printed wiring board, especially, to a built-up multilayered printed wiring board suitable to be used as a packaging substrate to mount IC chips.
2. Discussion of the Background
Japanese Unexamined Patent Publications 2001-127435 and 2002-208778 are directed to a built-up multilayered printed wiring board (hereinafter referred to as a “multilayered PWB”) having through-holes and conductive layers covering through-hole surfaces. Japanese Unexamined Patent Publication H11-251749 is directed to a multilayered PWB having a via hole filled with conductive material. The contents of these publications are incorporated herein by reference in their entirety.